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Next: Initial and boundary conditions Up: Model description Previous: Computational grid   Index

Input grids and data


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              | BOTtom      |
              |             |
              | WLEVel      |
              |             |
              |  | CURrent  |
              | <           |
              |  | VX       |
              |  | VY       |
              |             |
              | FRiction    |
              |             |
              |  | WInd     |
INPgrid     (<  <            >)                                             &
              |  | WX       |
              |  | WY       |
              |             |
              | PRessure    |
              |             |
              | POROsity    |
              |             |
              | PSIZe       |
              |             |
              | HSTRUCture  |
              |             |
              | NPLAnts     |

   | -> REGular [xpinp] [ypinp] [alpinp] [mxinp] [myinp] [dxinp] [dyinp] |
  <                                                                       > &
   |    CURVilinear  STAGgered                                           |

    (EXCeption  [excval])                                                   &

                                        | -> Sec  |
    (NONSTATionary [tbeginp] [deltinp] <     MIn   >  [tendinp])
                                        |    HR   |
                                        |    DAy  |

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OPTION CURVILINEAR NOT FOR 1D-MODE.


With this required command the user defines the geographic location, size and orientation of an input grid and also the time characteristics of the variable if it is not stationary. If this is the case (the variable is not stationary), the variable should be given in a sequence of fields, one for each time step [deltinp]. The actual reading of values of bottom, wind, pressure, etc. from file is controlled by the command READINP.
This command INPGRID must precede the following command READINP.


There can be different grids for bottom level (BOTTOM), current (CURRENT), bottom friction coefficient (FRICTION), wind velocity (WIND), atmospheric pressure (PRESSURE), porosity layers (POROSITY), stone diameters (PSIZE), heights (HSTRUCTURE) of porous structures and vegetation density (NPLANTS).


If the current velocity components are available on different grids, then option VX, VY can define these different grids for the x - and y -component of the current, respectively (but the grids must have identical orientation). Different grids for VX and VY may be useful if the data are generated by a circulation model using a staggered grid. The same holds for the wind velocity components, i.e. WX and WY.


In the case of a regular grid (option REGULAR in the INPGRID command) the current and wind velocity vectors are defined with the x - and y -component of the current or wind vector with respect to the x -axis of the input grid. In case of an orthogonal curvilinear grid (option CURVILINEAR in the INPGRID command) the current and wind velocity vectors are defined with the x - and y -component of the current or wind vector with respect to the x -axis of the problem coordinate system.


Porosity layers can be placed inside the computational domain to simulate reflection and transmission effects of porous structures such as rubble mound breakwaters and jetties. Porosity is defined as the volumetric porosity of the structures and its value is in between 0 and 1. A porosity value of 0.45 is typically used for breakwaters. A small value (< 0.1) should be interpreted as impermeable, like walls and dams. Also structure heights (relative to the bottom) can be specified so that both submerged and emerged breakwaters is allowed.


If the user specifies an input grid for the atmospheric pressure, then an input grid for wind must be included as well. Both space varying wind and pressure may be read from a meteorological file.


For wind velocity, friction coefficient, grain size, height of porous structures and vegetation density it is also possible to use a constant value over the computational field (see commands WIND, FRICTION, POROSITY and VEGETATION, respectively). No grid definition for wind, friction, grain size, structure height or vegetation density is then required.


Note that in case of options BOTTOM, POROSITY, PSIZE, HSTRUCTURE and NPLANTS only stationary input field is allowed.


If land points remain dry during the computation (no flooding!), then these points can be ignored. In this way, simulation time and internal memory can be saved. This can be done by indicating bottom level in these points as exception value. See command INPGRID BOTTOM EXCEPTION. For parallel runs using MPI, an exception value for bottom levels should be prescribed in order to have a good load-balancing!


Exception value for bottom levels can also be used to take into account dams, screens, quays or jetties in the domain. In addition, they may represent small obstacles with subgrid dimensions that possibly influence the local flow pattern. In this way, the user can defined a line of thin dams that separate the flow on both sides.


See Section 2.5.3 for more information on input grids.

BOTTOM defines the input grid of the bottom level. (For the definition of the bottom  
  level, see command READINP).  
WLEV defines the input grid of the water level. (For the definition of the water  
  level, see command READINP).  
CURRENT defines the input grid of the current field (same grid for x - and y -components).  
VX defines the input grid of the x -component of the current field (different grid  
  than y -component but same orientation).  
VY defines the input grid of the y -component of the current field (different grid  
  than x -component but same orientation).  
FRICTION defines the input grid of the bottom friction coefficient (defined in command  
  FRICTION, not to be confused with this option FRICTION!).  
WIND defines the input grid of the wind velocity field (same grid for x - and  
  y -component).  
  If neither of the commands WIND and READINP WIND is used it is assumed  
  that there is no wind.  
WX defines the input grid of the x -component of the wind velocity field  
  (different grid than y -component but same orientation).  
WY defines the input grid of the y -component of the wind velocity field  
  (different grid than x -component but same orientation).  
PRESSURE defines the input grid of the atmospheric pressure. (For the definition of  
  the atmospheric pressure, see command READINP).  
POROSITY defines the input grid of the porosity distribution.  
  If neither of the commands POROSITY and READINP POROSITY is used it is  
  assumed that there is no porous structure.  
PSIZE defines the input grid of the grain sizes of porous structures.  
HSTRUCTURE defines the input grid of the heights of porous structures.  
NPLANTS defines input grid of the horizontally varying vegetation density (defined  
  in command VEGETATION).  
REGULAR means that the input grid is uniform and rectangular.  
[xpinp] geographic location (x -coordinate) of the origin of the input grid in  
  problem coordinates (in m) if Cartesian coordinates are used or in degrees if  
  spherical coordinates are use (see command COORD).  
  Default: [xpinp] = 0. In case of spherical coordinates there is no default, the  
  user must give a value.  
[ypinp] geographic location (y -coordinate) of the origin of the input grid in  
  problem coordinates (in m) if Cartesian coordinates are used or in degrees if  
  spherical coordinates are use (see command COORD).  
  Default: [ypinp] = 0. In case of spherical coordinates there is no default, the  
  user must give a value.  
[alpinp] direction of the positive x -axis of the input grid (in degrees, Cartesian convention).  
  See command COORD.  
  Default: [alpinp] = 0.  
[mxinp] number of meshes in x -direction of the input grid (this number is one less  
  than the number of grid points in this direction!).  
[myinp] number of meshes in y -direction of the input grid (this number is one less  
  than the number of grid points in this direction!).  
  In 1D-mode, [myinp] should be 0.  
[dxinp] mesh size in x -direction of the input grid,  
  in m in case of Cartesian coordinates or  
  in degrees if spherical coordinates are used, see command COORD.  
[dyinp] mesh size in y -direction of the input grid,  
  in m in case of Cartesian coordinates or  
  in degrees if spherical coordinates are used, see command COORD.  
  In 1D-mode, [dyinp] may have any value.  
  Default: [dyinp] = [dxinp].  
CURVILINEAR means that the input grid is curvilinear; this option is available only if the  
  computational grid is curvilinear as well. The input grid is identical  
  to the computational grid.  
  NOT FOR 1D-MODE.  
STAGGERED means that the input grid of a grid-oriented (not Cartesian!) velocity  
  component u or v is staggered in y - or x -direction, respectively.  
  The velocity components are given in their points of definition according  
  to the Arakawa C-grid staggering.  
  NOT FOR 1D-MODE.  
EXCEPTION certain points inside the given grid that are to be ignored during the  
  computation can be identified by means of an exception value as given in  
  the corresponding input file as controlled by the command READINP.  
  NOT FOR 1D-MODE.  
[excval] exception value; required if the option EXCEPTION is used.  
  Note: if [fac] $ \neq$ 1 (see command READINP), [excval] must be given as  
  [fac] times the exception value.  
NONSTATION the variable is nonstationary (given in a time sequence of fields).  
  NOT FOR 1D-MODE.  
[tbeginp] begin time of the first field of the variable, the format is:  
  1 : ISO-notation 19870530.153000  
  2 : (as in HP compiler) '30-May-87 15:30:00'  
  3 : (as in Lahey compiler) 05/30/87.15:30:00  
  4 : 15:30:00  
  5 : 87/05/30 15:30:00'  
  6 : as in WAM 8705301530  
  7 : 153000.000  
  This format is installation dependent. See Implementation Manual or ask the  
  person who installed SWASH on your computer. Default is option 7.  
[deltinp] time interval between fields, the unit is indicated in the next option:  
  SEC unit seconds  
  MIN unit minutes  
  HR unit hours  
  DAY unit days  
[tendinp] end time of the last field of the variable, the format is:  
  1 : ISO-notation 19870530.153000  
  2 : (as in HP compiler) '30-May-87 15:30:00'  
  3 : (as in Lahey compiler) 05/30/87.15:30:00  
  4 : 15:30:00  
  5 : 87/05/30 15:30:00'  
  6 : as in WAM 8705301530  
  7 : 153000.000  
  This format is installation dependent. See Implementation Manual or ask the  
  person who installed SWASH on your computer. Default is option 7.  


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          |  BOTtom      |
          |              |
          |  WLEVel      |
          |              |
          |  CURrent     |
          |              |
          |  FRiction    |
          |              |           |  'fname1'            |
READinp  <   WInd         >  [fac]  <                        >   [idla]     &
          |              |           |  SERIes   'fname2'   |
          |  PRessure    |
          |              |
          |  POROsity    |
          |              |
          |  PSIZe       |
          |              |
          |  HSTRUCture  |
          |              |
          |  NPLAnts     |

                                           | -> FREe                       |
                                           |                               |
                                           |                 | 'form' |    |
           [nhedf] ([nhedt]) ([nhedvec])  <     FORmat      <          >    >
                                           |                 | [idfm] |    |
                                           |                               |
                                           |    UNFormatted                |

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With this required command the user controls the reading of values of the indicated variables from file. This command READINP must follow a command INPGRID.


If the variables are in one file, then the READINP commands should be given in the same sequence as the sequence in which the variables appear in the file.

BOTTOM with this option the user indicates that bottom levels (in m) are to be read from  
  file (bottom level positive downward relative to an arbitrary horizontal datum  
  level). The sign of the input can be changed with option [fac] = -1. (see below).  
WLEV with this option the user indicates that water levels (in m) are to be read from  
  file (water level positive upward relative to the same datum level as used in  
  option BOTTOM). Sign of input can be changed with option [fac] = -1. If the  
  water level is constant in space and time, the user can use the command SET  
  to add this (still) water level to the still water depth.  
CURRENT rectilinear (curvilinear) input grid: with this option the user indicates that  
  the x - and y -component ($ \xi$ - and $ \eta$ -component) (in m/s) are to be read from  
  one and the same file (with one READINP command). With this option SWASH  
  reads first all x -components ($ \xi$ -components), and then all y -components  
  ($ \eta$ -components) (see below). The first component (x - or $ \xi$ -component) is  
  always eastward oriented and the second one (y - or $ \eta$ -component) is always  
  northward oriented. The components $ \xi$ and $ \eta$ are taken along the directions of  
  the grid lines of the curvilinear grid!  
FRICTION with this option the user indicates that friction coefficient is to be read from  
  file for Manning or Chezy formula's or Nikuradse roughness height. If the  
  coefficients are constant in space and time: see command FRICTION.  
WIND rectilinear (curvilinear) input grid: with this option the user indicates that  
  the x - and y -component ($ \xi$ - and $ \eta$ -component) (in m/s) are to be read from  
  one and the same file (with one READINP command). With this option SWASH  
  reads first all x -components ($ \xi$ -components), and then all y -component  
  ($ \eta$ -components) (see below). The components $ \xi$ and $ \eta$ are taken along the  
  directions of the grid lines of the curvilinear grid! If the wind is constant, see  
  command WIND.  
PRESSURE with this option the user indicates that atmospheric pressures (in N/m2) are  
  to be read from file. Unit can be changed with option [fac] (see below).  
POROSITY with this option the user indicates that volumetric porosity is to be read from  
  file. Porosity values less than 1 indicates the location of porous structures. A  
  value of 1 represents water points. Regions with small porosity values (< 0.1)  
  should be treated as impermeable regions, i.e. land points.  
PSIZE with this option the user indicates that grain sizes (in m) of porous structures  
  are to be read from file. If the grain size is constant for all porous structures  
  then see command POROSITY for specification.  
HSTRUCTURE with this option the user indicates that heights (in m) of porous structures  
  (relative to the bed level) are to be read from file. If the height is constant  
  for all porous structures then see command POROSITY for specification.  
NPLANTS with this option the user indicates that horizontally varying vegetation  
  density (per m2) is to be read from file. If the density is constant then  
  see command VEGETATION for specifcation.  
[fac] SWASH multiplies all values that are read from file with [fac]. For instance  
  if the bottom levels are given in unit decimeter, one should make [fac]=0.1 to  
  obtain levels in m. To change sign of bottom level use a negative value of [fac].  
  Note that [fac] = 0 is not allowed!  
  Default: [fac]=1.  
'fname1' name of the file with the values of the variable.  
SERIES with this option (only for MODE NONSTATIONARY) the user indicates that the  
  names of the files containing the nonstationary variable(s) are located in a  
  separate file with name 'fname2' (see below).  
'fname2' name of file that contains the names of the files where the variables  
  are given. These names are to be given in proper time sequence. SWASH reads  
  the next file when the previous file end has been encountered. In these files the  
  input should be given in the same format as in the above file 'fname1' (that  
  implies that a file should start with the start of an input time step).  
[idla] prescribes the order in which the values of bottom levels and other fields  
  should be given in the file.  
  =1: SWASH reads the map from left to right starting in the upper-left-hand  
  corner of the map (it is assumed that the x -axis of the grid is pointing  
  to the right and the y -axis upwards). A new line in the map should  
  start on a new line in the file. The lay-out is as follows:  
  1,myc+1 2,myc+1 ... mxc+1, myc+1  
  1,myc 2,myc ... mxc+1, myc  
  ... ... ... ...  
  1,1 2,1 ... mxc+1, 1  
     
  =2: as [idla]=1 but a new line in the map need not start on a new line in  
  the file.  
  =3: SWASH reads the map from left to right starting in the lower-left-hand  
  corner of the map. A new line in the map should start on a new line in  
  the file. The lay-out is as follows:  
  1,1 2,1 ... mxc+1, 1  
  1,2 2,2 ... mxc+1, 2  
  ... ... ... ...  
  1,myc+1 2,myc+1 ... mxc+1, myc+1  
     
  =4: as [idla]=3 but a new line in the map need not start on a new line  
  in the file.  
  =5: SWASH reads the map from top to bottom starting in the lower-left-hand  
  corner of the map. A new column in the map should start on a new line in  
  the file. The lay-out is as follows:  
  1,1 1,2 ... 1, myc+1  
  2,1 2,2 ... 2, myc+1  
  ... ... ... ...  
  mxc+1,1 mxc+1,2 ... mxc+1, myc+1  
     
  =6: as [idla]=5 but a new column in the map need not start on a new line  
  in the file.  
  Default: [idla]=1  
[nhedf] is the number of header lines at the start of the file. The text in the header  
  lines is reproduced in the PRINT file created by SWASH (see Section 3.3). The  
  file may start with more header lines than [nhedf] because the start of the  
  file is often also the start of a time step and possibly also of a vector  
  variable (each having header lines, see below, [nhedt] and [nhedvec]).  
  Default: [nhedf]=0  
[nhedt] only if variable is time dependent: number of header lines in the file at the  
  start of each time level. A time step may start with more header lines than  
  [nhedt] because the variable may be a vector variable which has its own header  
  lines (see below [nhedvec]).  
  Default: [nhedt]=0  
[nhedvec] for each vector variable: number of header lines in the file at the start of  
  each component (e.g., x - or y -component).  
  Default: [nhedvec]=0  
FREE With this option the user indicates that the values are to be read with free  
  format. Free format is a standard of the computer programming language  
  FORTRAN. The free format conventions in reading from a file are almost the  
  same as the conventions for the command syntax given elsewhere in this manual;  
  the most important differences are:  
  1. There are no continuation marks, reading continues until the required  
  number of data has been read, or until a slash (/) is encountered.  
  2. Input lines can be longer than 80 characters (depending on the operating  
  system of the computer).  
  3. Comment is not allowed.  
  With free format empty fields, repetition factors, and closure of a line by a slash,  
  can be used.  
FORMAT with this option the user indicates that fixed format (FORTRAN convention) is  
  to be used when reading the values from file. The format can be defined in one  
  of two ways, by giving the format number [idfm] or the format string 'form'.  
'form' a user-specified format string according to Fortran convention, e.g.  
  '(10X,12F5.0)'.  
[idfm] this format number is interpreted as follows:  
  =1: Format according to BODKAR convention (a standard of the Ministry  
  of Transport and Public Works in the Netherlands).  
  Format string: (10X,12F5.0).  
  =5: Format (16F5.0), i.e. an input line consists of 16 fields of 5 places each.  
  =6: Format (12F6.0), i.e. an input line consists of 12 fields of 6 places each.  
  =8: Format (10F8.0), i.e. an input line consists of 10 fields of 8 places each.  
UNFORMATTED is a form of reading without conversion (binary files). Not recommended for  
  ordinary use.  

If the file does not contain a sufficient number of data (i.e. less than the number of grid points of the input grid), SWASH will write an error message to the PRINT file, and if [itest]>0 (see command TEST) it will reproduce the data in the PRINT file, using the lay-out according to [idla]=1. This echo of the data to print file is also made if the READINP command is embedded between two TEST commands in the command file as follows:
   TEST 120
   READINP ....
   TEST 0


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           | SALinity    |
           |             |
INPtrans  <  TEMPerature  >                                                 &
           |             |
           | SEDiment    |


   | -> REGular [xpinp] [ypinp] [alpinp] [mxinp] [myinp] [dxinp] [dyinp] |
  <                                                                       > &
   |    CURVilinear                                                      |

    (EXCeption  [excval])                                                   &

    (NONUNIForm  [kmax])

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OPTION CURVILINEAR NOT FOR 1D-MODE.


With this command the user defines the geographic location, size and orientation of a stationary input grid for the transport of constituent. This input grid thus supplies initial and stationary boundary conditions for the considered constituent. The actual reading of constituent values from file is controlled by the command READTRANS.
This command INPTRANS must precede the following command READTRANS.


There can be different grids for salinity (SALINITY), temperature or heat (TEMPERATURE) and suspended sediment load (SEDIMENT).


See command INPGRID for the description of the options in this command INPTRANS.


See Section 2.5.4 for more information on (input) grids for transport of constituents.

NONUNIFORM the constituent is nonuniform in vertical.  
[kmax] the number of layers representing the number of input fields as given in  
  a sequence (see command READTRANS). This number must be equal to the  
  number of vertical layers in multi-layered mode (see command VERTICAL)  
  or 1 (i.e. uniform in vertical).  
  Default: [kmax] = 1  


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            |  SALinity    |
            |              |           | 'fname1'          |
READtrans  <   TEMPerature  >  [fac]  <                     >  [idla]       &
            |              |           | LAYers   'fname2' |
            |  SEDiment    |

                                       | -> FREe                       |
                                       |                               |
                                       |                 | 'form' |    |
                              [nhedf]  <     FORmat      <          >    >
                                       |                 | [idfm] |    |
                                       |                               |
                                       |    UNFormatted                |

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With this command the user controls the reading of initial and boundary values of transport constituents from file. This command READTRANS must follow a command INPTRANS.


The constituents that can be read are salinity (SALINITY) (in ppt, psu or kg/m3), temperature (TEMPERATURE) (in oC) and suspended sediment load (SEDIMENT) (in kg/m3).


See command READINP for the description of the options in this command READTRANS.

LAYERS with this option (only for multi-layered mode) the user indicates that the  
  names of the files containing the nonuniform constituent are resided in a  
  separate file with name 'fname2' (see below).  
'fname2' name of file that contains the names of the files where the constituents  
  are given. These names are to be given in proper sequence, i.e. from top  
  (first layer) to bottom (last layer). SWASH reads the next file when the  
  previous file end has been encountered. In these files the input should be  
  given in the same format as in the above file 'fname1'.  


next up previous index
Next: Initial and boundary conditions Up: Model description Previous: Computational grid   Index
The SWASH team 2017-04-06